Relay terminal, base station, charging server, communication system, charging method, program computer data signal, and storage medium

ABSTRACT

In a relay terminal A for relaying packet communication between a destination terminal C located outside a service area of a base station Z, and the base station Z, a contribution to relaying is measured and the measurement result is transmitted to a billing server SA configured to store an information communication charge of the relay terminal A, whereby it becomes feasible to give the relay terminal an incentive.

TECHNICAL FIELD

The present invention relates to a relay terminal, a base station, abilling server, a communication system, a billing method, a program, acomputer data signal, and a storage medium capable of establishing anoptional ad hoc network with a radio terminal (relay terminal) locatedin a service area in order to secure communication with a radio terminal(destination terminal), particularly, with a destination terminallocated outside the service area and making an information communicationcharge reflect a contribution to relaying, particularly, by the relayterminal on the occasion of determining the information communicationcharge during communication with the destination terminal.

BACKGROUND ART

An ad hoc network in a radio system is normally a network consisting ofonly radio terminals without intervention of a base station and, forcommunication with a radio terminal existing in a zone outside a reachof radio waves, i.e., in an uncommunicable zone, packets are transportedvia radio terminals existing between the source and destinationterminals, up to the destination, thereby securing communication.

Therefore, the radio terminals in the ad hoc network have the relayingfunction and share their own resources for communication of otherterminals. This ad hoc network is essentially a self-supporting systemlike LAN and system for easily constructing a network to secure acommunication area.

In recent years, however, studies are under way on applying thetechnology of such an ad hoc network to the public systems.

The application of the ad hoc network to the public services is mainlyto supplement service areas. It is not economical in terms of capitalinvestment to cover all the areas up to sites to which radio waves arehard to reach, e.g., behind buildings. The application of the ad hocnetwork technology can implement transfer from the system in which thenetwork is entirely in charge of the area covering function, to thesystem in which some radio terminals supplementally contribute to thefunction.

Techniques of controlling transport routes on the ad hoc network haveactively been studied as the most important technology for implementingthis system.

In the ad hoc network, where a radio terminal moves, or where thecommunication quality heavily degrades, a variety of controls becomenecessary: for example, it becomes necessary to change a transport routefrom the source radio terminal to the destination radio terminal toanother, to notify relay radio terminals of a forwarding address, and soon. Techniques for these controls can be settled by use of thetechnologies in wireless LAN, though there is the difference in thatcommunication is conducted via the base station in the public system,and a number of proposals have been made in practice (e.g., JapanesePatent Application Laid-Open No. 11-289349 and others).

DISCLOSURE OF THE INVENTION

In the application of the ad hoc network to the public communicationservices, however, there arises the problem that the battery of a radioterminal involved in relaying is discharged unawares because of therelaying to another radio terminal bearing no relation thereto. Therelaying can cause the radio resources to be divided, and possiblyresult in decreasing the communication speed of the radio terminalinvolved in the relaying.

Unless the terminal serving for the relaying for others is given someincentive, it is difficult to expand the service areas through the useof the ad hoc network in the public communication systems. There was noprior art for solving this problem and it was thus difficult to applythe ad hoc network technology to the public communication services.

Therefore, the present invention has been accomplished in view of theabove problem and an object of the present invention is to provide arelay terminal, a base station, a billing server, a communicationsystem, a billing method, a program, and a storage medium capable ofgiving an incentive to a radio terminal performing relaying for anotherradio terminal on a public network to which the ad hoc networktechnology is applied.

In order to solve the above problem, a relay terminal of the presentinvention is a relay terminal for relaying packet communication betweena destination terminal and the base station, the relay terminalcomprising: measuring means for measuring a contribution to therelaying; and transmitting means for transmitting a measurement resultof the contribution to a billing server connected to a network includingthe base station and configured to store an information communicationcharge of the relay terminal.

A base station according to the present invention is a base station forimplementing packet communication with a destination terminal through arelay terminal, the base station comprising: measuring means formeasuring a contribution to relaying by the relay terminal; andtransmitting means for transmitting a measurement result of thecontribution to a billing server connected to a network including thebase station and configured to store an information communication chargeof the relay terminal.

According to the present invention, the contribution to relaying ismeasured and it can be reflected in billing; therefore, it becomesfeasible to give the relay terminal an incentive in the billing server.

The contribution is preferably the number of packets relayed by therelay terminal and, in this case, the measuring means comprisesidentifying means for identifying whether a header included in thepackets is one associated with relaying; and a counter configured toincrement a count number thereof in proportion to the number of packetstransmitted and/or received during relaying when the identifying meansidentifies an occasion of relaying, and a value proportional to thecount number is transmitted as a measurement result of the of the numberof packets to the billing server. Since the number of packets can beaccurately measured, accurate billing can be performed based thereon.

Preferably, the transmitting means transmits the value proportional tothe count number along with identification information obtained by theidentifying means, as the measurement result to the billing server,whereby it becomes easier to implement the billing associated with theidentification information.

The contribution to the relaying may be a relay time and, in this case,the measuring means comprises identifying means for identifying whethera control message included in the packets represents a start ofcommunication or an end of communication; and calculating means forcalculating a time period between a receiving time of the controlmessage at the start of communication and a receiving time of thecontrol message at the end of communication, identified by theidentifying means, and the time period is transmitted as the relay timeto the billing server. When the control message is included in thepackets, it becomes feasible to implement simple contributiontransmission.

The contribution may also be an amount of power internally consumed inthe relay terminal during the relaying, whereby the user worrying aboutthe discharge of the battery can be given an incentive based thereon.

The contribution may also be an amount of radio resources used by therelay terminal, and the apparatus in this case is preferably configuredso that a communication system during the relaying is time divisionmultiple access and so that the measuring means comprises storage meansfor storing the number of timeslots, the number of carriers, and thenumber of frames, used in transmission and receiving of the packets; andcalculating means for calculating the amount of radio resources as thecontribution from the values stored in the storage means.

When the contribution is the amount of radio resources, the apparatusmay also be configured so that a communication system during therelaying is code division multiple access and so that the measuringmeans comprises storage means for storing the number of timeslots, thenumber of carriers, and the number of codes, used in transmission andreceiving of the packets; and calculating means for calculating theamount of radio resources as the contribution from the values stored inthe storage means.

In these cases, the user worrying about the use of radio resources canbe given an incentive.

When there are a plurality of mentioned relay terminals for relayingpackets, the measuring means of each mentioned relay terminal or thebase station may be configured to measure as the contribution a valueobtained by dividing a physical quantity used for communication in eachmentioned relay terminal, by the number of relay terminals, and in thiscase, by setting a total contribution to a predetermined value, it isfeasible to prevent the total incentive amount from increasingexcessively.

A communication system may be configured to comprise a base station forrelaying the measurement result transmitted from the foregoing relayterminal to the billing server.

A billing server according to the present invention is a billing serverfor storing an information communication charge of a relay terminal, thebilling server comprising: receiving means for receiving a contributionto relaying by the relay terminal for relaying packet communicationbetween a destination terminal and the base station; and billing meansfor effecting negative billing according to the contribution received bythe receiving means, on the information communication charge stored.

According to the present invention, execution of relaying results ineffecting negative billing, whereby it becomes feasible to implementprovision of an incentive to the relay terminal.

The amount of the negative billing may be set to a given value when thecontribution is not less than a reference value, or may be set to avalue proportional to a level of the contribution. In addition, theamount of the negative billing can also be set at or below apredetermined maximum amount.

The billing server of the present invention may also be configured sothat the contribution by the relay terminal is classified into one groupout of a plurality of groups obtained by dividing a set of contributionsof relay terminals according to the contributions and so that thenegative billing is effected based on a value of a base amountcorrelated with a weighting factor corresponding to each group. Thecorrelation can be multiplication. This can ensure fairness of billing.

The billing server can also be configured so that when the amount of thenegative billing is greater than the information communication chargestored in a predetermined period, a difference between the informationcommunication charge and the amount of the negative billing is storedfor a fixed period and the negative billing is effected on a nextinformation communication charge on the basis of the stored difference;this makes it feasible to carry the unused negative billing amount overinto the next charge.

A billing method of an information communication charge according to thepresent invention is a method comprising a step of storing aninformation communication charge of a relay terminal in a storagedevice; a step of receiving a contribution to relaying by the relayterminal for relaying packet communication between a destinationterminal and the base station; and a step of effecting negative billingcalculation according to the received contribution on the informationcommunication charge stored in the storage device.

According to the present invention, execution of relaying results ineffecting negative billing, whereby it becomes feasible to give anincentive to the relay terminal.

A program according to the present invention is a program for letting acomputer execute a step of storing an information communication chargeof a relay terminal in a storage device; and a step of receiving acontribution to relaying by the relay terminal for relaying packetcommunication between a destination terminal and the base station andeffecting negative billing calculation according to the receivedcontribution on the information communication charge stored in thestorage device, and a recording medium is a medium in which this programis recorded so that the computer can read.

Another relay terminal according to the present invention is a relayterminal for relaying packet communication between a destinationterminal and a base station, the relay terminal comprising: measuringmeans for measuring a contribution to relaying; and calculating meansfor calculating from a measurement result by the measuring means, avalue to be deducted from an information communication charge in abilling server connected to a network including the base station andconfigured to store the information communication charge of the relayterminal.

According to the present invention, the calculating means performs theabove calculation, whereby it is feasible to lessen the processing inthe billing server.

Another billing method of an information communication charge accordingto the present invention comprises a step of transmitting a contributionto relaying by a relay terminal for relaying packet communicationbetween a destination terminal and a base station, from the relayterminal; and a step of effecting negative billing calculation accordingto the contribution, on an information communication charge stored in apredetermined storage device.

According to the present invention, execution of relaying results ineffecting negative billing, whereby it becomes feasible to give anincentive to the relay terminal.

The billing method of the information communication charge according tothe present invention can be configured to comprise an identificationstep of identifying whether a header included in the packets is oneassociated with relaying; and a step of incrementing a count number of acounter in proportion to the number of packets transmitted and/orreceived during relaying when the identification step results inidentifying an occasion of relaying, and the transmitting step is totransmit a value proportional to the count number as the contribution;in this case, the number of packets can be measured accurately wherebyaccurate billing can be implemented.

When the destination terminal is located outside a service area of thebase station, the measuring means of the relay terminal can measure thecontribution.

When the destination terminal is located outside the service area of thebase station, the measuring means of the base station can measure thecontribution.

When the destination terminal is located outside the service area of thebase station, the receiving means of the billing server can receive thecontribution.

In the billing method of the information communication charge, thecontribution receiving step can also be carried out when the destinationterminal is located outside the service area of the base station.

The contribution receiving step executed by a computer data signal canbe carried out when the destination terminal is located outside theservice area of the base station. The contribution transmitting stepexecuted in the billing method of the information communication chargecan be carried out when the destination terminal is located outside theservice area of the base station.

A program of the present invention is a program for letting a computerexecute a step of storing an information communication charge of a relayterminal in a storage device; and a step of receiving a contribution torelaying by the relay terminal for relaying packet communication betweena destination terminal and a base station and effecting negative billingcalculation according to the received contribution on the informationcommunication charge stored in the storage device.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a system configuration diagram according to an embodiment.

FIG. 2 is a block diagram of a relay terminal.

FIG. 3 is an explanatory diagram showing a configuration in which therelay amount is measured during transmission or during receiving at arelay terminal.

FIG. 4 is an explanatory diagram showing a configuration in which therelay amount is measured during communication with a base station or adestination terminal at a relay terminal.

FIG. 5 is a flowchart to illustrate a method of measuring the number ofrelayed packets.

FIG. 6 is a block diagram of a relay terminal.

FIG. 7 is a block diagram of a base station configured so as not tomeasure the relay amount.

FIG. 8 is an explanatory diagram showing a configuration in which therelay amount is measured at a base station.

FIG. 9 is an explanatory diagram to illustrate an operation duringmultihop-base relaying.

FIG. 10 is a block diagram of a base station configured to measure therelay amount.

FIG. 11 is a block diagram of an incentive management system.

FIG. 12 is a flowchart to illustrate the charge calculating process.

FIG. 13 is a flowchart to illustrate the charge calculating process.

FIG. 14 is a system configuration diagram according to an embodiment.

BEST MODE FOR CARRYING OUT THE INVENTION

A relay terminal, a base station, a billing server, a communicationsystem, a billing method, a program, and a storage medium according toan embodiment will be described below. The same elements will be denotedby the same reference symbols, without redundancy of description.

FIG. 1 is a system configuration diagram according to an embodiment. Thebase station Z has one cell (service area: zone where radio terminalsare communicable with the base station Z) X. Let us assume herein thatin the cell X there exist terminal A and terminal B and outside the cellX there exists terminal C. The base station Z is connected to a networkN and a billing server SA is connected to the network N. These devicesare communicable with each other through the network N.

First, normal communication will be described. A variety of conceivablestructures are available for the network N, but the network N herein isassumed to be a PDC packet communication network permitting billingbased on the amount of information. It is assumed that physical channelsfor packet communication have the frame structure of 3-channel timedivision multiple access (TDMA) and up to three slots are simultaneouslyaccessible in order to achieve increase in data transmission speed bymultislot transmission.

In the case where a specific terminal Q connectible to the network Ntransmits packets to the terminal A in the cell X, the terminal Q firstaccesses a packet subscriber processing module (PPM: not shown) in thenetwork N through a neighbor base station, to effect packetcommunication registration with PPM. PPM, receiving a registrationrequest, registers progress of packet communication with a mobilecommunication service control point (M-SCP: not shown) in the network Nand retrieves user information of the terminal Q from M-SCP to executeauthentication of the user. When the validity of the user isauthenticated, PPM performs a link connection transaction to packetgateway processing equipment (PGW: not shown) located between PPM andM-SCP and sends a packet communication registration response to theterminal Q to initiate packet communication.

For ending packet transmission from the terminal Q, a packetcommunication registration cancellation request, instead of the packetcommunication registration request, is transmitted to PPM and inresponse thereto PPM sends a packet communication cancellation requestto M-SCP. Receiving a response to acknowledge the communicationcancellation request from M-SCP, PPM sends a packet communicationregistration cancellation response to the terminal Q and the terminal Qsends a packet communication registration cancellation acknowledgment toPPM. Then PPM performs a link disconnection transaction to PGW toterminate the packet communication.

For forwarding packets from the terminal Q to the terminal A, PGWidentifies an IP address included in the received packets, accessesM-SCP on the basis of this address, acquires subscriber information,location information, etc. of the terminal A stored in M-SCP, forwardsthe packets from the terminal Q to PPM where the terminal A is located,and transmits the packets to the terminal A through the base station Zwhere the terminal A is located.

Each packet contains data and a header including at least a destinationaddress, a source address, and a number indicating a packet order, andin the network N packets are forwarded in frame structure. A framecontains source and destination addresses, various control bits, data asinformation to be transmitted, and an error-detection code sequencebetween flags indicating the start and end of a packet.

After the terminal A starts receiving packets from the base station Zand when the terminal A sends to the base station Z a packet with aheader containing information of a packet communication registrationcancellation acknowledgment along with the address information andregistration number of the terminal A, M-SCP is notified of the numberof packets received by the terminal A and the number of received packetsis stored along with the user registration information in M-SCP.

The billing server SA is installed in M-SCP or separately from theM-SCP, and a billing management system SA1 in the billing server SAperforms billing in proportion to the number of stored packets, as aninformation communication charge. This information communication chargeis stored with the user registration information in a storage device ofthe billing management system SA1.

Now let us explain a case where data transmission is carried out fromthe terminal Q to the terminal C located outside the cell X of the basestation Z. When packets are transmitted from the specific terminal Q onthe network N via the base station Z to the terminal C, packetcommunication is usually infeasible, because the terminal C is locatedoutside the cell X of the base station Z.

Then let us suppose that packets addressed to the terminal C are relayedon the basis of destination address information added to the receivedpackets by the terminal A present in the area X, whereby the packets areforwarded to the terminal C of the destination. A response from theterminal C is relayed by the terminal C present in the cell X and issent via the base station Z to the terminal and the billing server SA onthe network N. The operation will be detailed below. Each terminalperforming relaying like the terminal A and the terminal B will bereferred to as a relay terminal, and the terminal C of the destinationof packets as a destination terminal.

PGW located upstream of the base station Z identifies an IP addressincluded in the packets received from the terminal Q, accesses M-SCP onthe basis of this address, and attempts to acquire the subscriberinformation and location information of the terminal C stored in M-SCP.

When the location information of the terminal C is unknown, PGWestimates a PPM where the terminal C is expected to be located, on thebasis of past location information, and sends a signal to request aconfirmation for whether communication with the terminal C is possible,to appropriate terminals A, B located in the cell X of the base stationZ located downstream of the PPM. In response to this signal, theterminals A, B for relaying check with the terminal C.

When receiving a response of “communicable” from the terminal C, theterminals A, B notify the PPM of the fact, and the PPM rewrites thelocation information of the terminal C stored in M-SCP so as to indicatethe communicable location through the base station Z by relaying via therelay terminals A, B.

Thereafter, the PPM adds an address of the terminal A being a downwardcommunication relay address, an address of the terminal B being anupward communication relay address, and a flag indicating application ofrelaying, in addition to the address of the terminal C being a targetaddress, to the header of the packets transmitted from the terminal Qand forwards the packets via the base station Z to the terminal Aaccording to the address of the terminal A.

The terminal A recognizes that the received packets are those to berelayed, and forwards the packets to the terminal C according to theaddress of the terminal C included in the header. The procedure ofcommunication is the same as that between the terminal A and the basestation Z, and the terminal C, after receiving the packets, creates apacket containing data of packet communication registration cancellationacknowledgment information and the header containing the address of theterminal B for relaying, the address and registration number of theterminal C itself, and the flag indicating application of relaying andsends it to the terminal B.

The terminal B recognizes the flag for application of relaying and sendsthe received packet to the base station Z. In response thereto, the basestation Z executes disconnection of the link to PGW through the PPM, soas to terminate the relayed communication.

FIG. 1 illustrates the case where the different relay terminals A, B areused between in the “up direction” in which packets are transmittedtoward the base station Z and in the “down direction” in which packetsare transmitted from the base station Z. Therefore, the base station Z,terminal A, and terminal C constitute one ad hoc network, while the basestation Z, terminal B, and terminal C another ad hoc network.

It is also possible to use the same relay terminal for the both upwardand downward communications. For example, where the terminal A relayspackets in both the up direction and down direction, only one ad hocnetwork configuration consisting of the base station Z, terminal A, andterminal C will suffice.

Accordingly, the upward and downward communication operations can behandled independently of each other in the present example. It is alsonoted that a plurality of relay terminals can be involved incommunication in either direction. As described above, the relayterminals B, C can implement virtual expansion of the cell X which isthe original cell of the base station Z.

Billing will be described below. An incentive management system SA2 isconnected on the network N. When communication is effected with therelay terminals, the incentive management system SA2 collects the resultof measurement of quantities indicating levels of relaying, measured ateach equipment such as the base station Z, the relay terminals A, B, orthe destination terminal C. The system determines incentive amounts onthe basis of the collected information.

An incentive is a benefit given according to the contribution of theterminal A or B during the relaying operation, and an incentive amountrepresents a degree of the contribution to the relaying. The billingserver SA determines an information communication charge whilereflecting the determined incentive amount in billing.

For performing the billing, contributions of the respective terminals A,B to relaying are first measured. The measurement of contributions canbe carried out at the base station Z or at the relay terminals A, B.

First described is a case where the relay terminals A, B themselvesmeasure their contributions. There are a number of measurable parametersfor determining the contributions. For example, the parameters includethe volume of data relayed by each relay terminal, i.e., the number ofrelayed packets, a time of relaying (relay time), the amount of radioresources used for relaying, the transmit power, the amount of batteryconsumption, the throughput during relaying, speed of relaying, and soon. A typical example is the number of packets. The following is thedetails.

FIG. 2 is a block diagram of the relay terminal A or B, which isprovided with a central processing unit CPU, a memory MEM, and aninterface I/F inside a housing KY. The CPU performs data communicationwith a transmission device (transmitting means) ATt mounted on thehousing KY, through the interface I/F, and the transmission device ATttransmits packets received from the outside, to the CPU and transmitspackets received from the CPU, to the outside.

This relay terminal A, B is a relay terminal A, B for relaying packetcommunication between the destination terminal C located outside thecell X of the base station Z, and the base station Z, and is providedwith the measuring means (CPU and memory MEM) for measuring acontribution to relaying, and the transmitting means ATt fortransmitting the measurement result to the billing server SA connectedto the network N including the base station Z and configured to storethe information communication charge of the relay terminal A, B. Sincethe contribution to relaying is measured, it can be reflected inbilling, so that an incentive can be given to the radio terminal A, Bperforming the relaying for the other radio terminals Q, C, on thepublic network.

The contribution herein is assumed to be the number of packets relayedby the relay terminal A, B. The CPU identifies whether the headerincluded in the received packets is one associated with relaying, on thebasis of an identifier (identifying means), and is provided with acounter (which is an internal action of CPU) configured to increment acount number in proportion to the number of packets transmitted and/orreceived during relaying when the identifying means identifies anoccasion of relaying. The CPU transmits a value proportional to thiscount number as a measurement result of the number of packets(contribution) to the incentive management system SA2 of the billingserver SA.

The relay terminal A, B can also add the number of packets as acontribution to the header of a packet immediately after completion ofthe relaying, after a lapse of an adequate period since completion ofthe relaying, or during the relaying, but the relay terminal hereincreates a message containing information about the number of packets andtransmits this message to the billing server SA. The transmission deviceATt transmits the value proportional to the count number as themeasurement result of the contribution along with the identificationinformation by the identifying means (CPU) to the billing server SA. Inthis method, since the number of packets can be measured accurately, itbecomes feasible to implement accurate billing and facilitate thebilling associated with the identification information.

For example, where there is the identification information indicatingrelaying, the billing management system SA1 or incentive managementsystem SA2 of the billing server SA effects negative billing calculationon the original information communication charge of the relay terminalA, B stored, on the basis of the contribution received by the incentivemanagement system SA2.

For example, when the number of packets is given the minus sign andtransmitted to the incentive management system SA2, the billingmanagement system SA1 or incentive management system SA2 calculates anegative information communication charge, thereby implementing negativebilling.

There are a variety of methods of measuring the above contribution. Inthe case where contributions are measured while discriminatingtransmission from receiving of packets, as shown in FIG. 3, themeasurement upon transmission is conducted at the time of forwarding (ortransmitting) packets to the base station Z or to the destinationterminal C, while the measurement upon receiving is conducted at thetime of receiving packets from the base station Z or from thedestination terminal C. By measuring packets in either timing, i.e.,upon transmission or upon receiving, the number of packets used inrelaying can be measured in both the up and down directions.

In the case where the measurement is carried out while discriminatingrelaying directions during relaying to and from the base station Z fromthose to and from the destination terminal C, as shown in FIG. 4, thenumber of packets can be measured by performing the measurement whenpackets are transmitted to and received from the base station Z or whenpackets are transmitted to and received from the destination terminal C.Which equipment will transmit packets is determined upon determinationof the forwarding (relaying) route in construction of the ad hoc networkconfiguration, and the information thereof is normally included asidentifiers of sender and receiver in the relayed data (packets).Therefore, it is possible to implement the discrimination of the relaydirections as described above.

FIG. 5 shows a specific example of the case where the number of packetsis measured as a contribution. This example is based on the premise thatthe measurement is performed while discriminating transmission fromreceiving in relaying as shown in FIG. 3. At the time of transmission ofrelayed packets, the counter of the relay terminal A is reset at zero atfirst (S51), and, when receiving (transmission) of packets is started(S52), the count number is incremented by one at every transmission of arelayed packet (S53).

When the counter up to K is counted up to K (S54), i.e., immediatelybefore reset, the counter notifies the base station Z of an output pulseindicating the completion of count-up and the identifier of the terminalA, B (S55). Since the number of packets is the product of the countnumber (K) and output pulses indicating completion of count-ups, thevalue proportional to the count number is transmitted to the billingserver SA as a result.

The example of FIG. 5 will be described below on the premise of the casewhere the measurement is performed while discriminating the relaydirections A, B as shown in FIG. 4. At first the counter is reset atzero (S51), and upon transmission and receiving of relayed packets, therelay terminal A confirms that the sender of the relayed packets is thebase station Z, from the header thereof. When the sender is the basestation Z (S52), the counter is incremented by one (S53).

When the counter up to K is counted up to K (S54), the counter notifiesthe base station Z of an output pulse indicating the completion ofcount-up and the identifier of the terminal A (S55). When the sender isnot the base station but the destination terminal C, the relay terminalB transmits the value proportional to the count number, as in the caseof the relay terminal A.

The incentive management system SA2 memorizes the number ofnotifications of output pulses indicating completion of count-ups fromthe counter and can calculate the number of relayed packets according to(the number of notifications)×(count number).

When the measurement is carried out at the relay terminals, themeasurement result is transmitted via the base station to the incentivemanagement system SA2; when the measurement is done at the base station,the measurement result is directly transmitted to the incentivemanagement system SA2. This transmission does not have to be carried outat frequent intervals. A plurality of transmission times, e.g., times ofchange of date, occasions before OFF of power, etc., can be setindependently of the value of the measurement result, and themeasurement result can be transmitted at least once within a period ofcalculation of a charge amount. The above counter can be reset after thetransmission of the measurement result.

As described above, when the contribution is measured at the relayterminal A, B, the measurement result of the contribution (the number ofpackets or the value proportional thereto) and the identifier toidentify the relay terminal A, B are transmitted to the base station Z,and the base station Z transmits these to the incentive managementsystem SA2 connected to the network N. The incentive management systemSA2 memorizes the above measurement result corresponding to theidentifier of the relay terminal A, B. The identifier of each terminalequipment can be one of a terminal number, an IP address, a subscriber(registration) number, etc. commonly used.

The contribution can be a relay time instead of the number of packets.In this case, the CPU as the measuring means identifies whether thecontrol message in the header of the packets received during relayingrepresents a start of communication or an end of communication(identifying means), calculates a time period between a receiving timeof the control message at the start of communication and a receivingtime of the control message at the end of communication, identified bythe identifying means, (calculating means), and sends this time periodas the relay time to the billing server SA. In this case, simplecontribution transmission can be achieved when the control message isincluded in the packets. The billing server SA effects negative billingproportional to the relay time.

The relay time can be measured in the above-stated configuration in thecase where one relay terminal A is involved in the upward and downwardcommunications; whereas, in the case where the relay terminal A is incharge of only downward communication, the measurement can beimplemented by adding the control message indicating an end ofcommunication, to the header of the last packet transmitted from theterminal Q. In the case where the relay terminal B is in charge of onlyupward communication, the measurement can be implemented by adding thecontrol message indicating an end of communication, to the header of thelast packet transmitted from the terminal C.

In systems without transmission and receiving of these control messages,the relay time is measured as follows. Since the communication systemduring relaying is the time division multiple access (TDMA), forexample, supposing three unit timeslots (Ts) are used by ten frames, therelay time can be calculated according to 3×Ts×10. Here Ts is the lengthof a unit timeslot (unit: second).

For measuring the relay time, it is necessary to measure a period oftime from start to end of communication; when the relay terminal A, Brelays the control messages representing the start and end ofcommunication like a connection request message and a disconnectionrequest message, the initiation and termination of the measurement canalso be timed with reference to these messages.

The above contribution may also be an amount of power internallyconsumed in the relay terminal during the relaying. In this case, theusers worrying about discharge of battery can be given incentives. TheCPU measures the amount of internally consumed power in the relayterminal A, B and transmits it as a contribution. The amount ofinternally consumed power can be measured based on a change of voltageof the battery not shown. A decrease of voltage results from an increasein the amount of internally consumed power.

The above contribution may also be an amount of radio resources used bythe relay terminal A, B. In this case, the users worrying about use ofradio resources can be given incentives. Since the communication systemduring the relaying is TDMA, the computer as the measuring means(including CPU) is provided with a memory MEM for storing the number oftimeslots, the number of carriers, and the number of frames, used intransmission and receiving of packets, and a CPU as the calculatingmeans for calculating the amount of radio resources as a contributionfrom the values stored in the memory MEM.

Namely, in the present example, supposing three timeslots are used byten frames, the amount of radio resources used is calculated accordingto 3×10× (the number of carriers used in each frame).

On the other hand, in the case where the communication system duringrelaying is (wideband) code division multiple access (CDMA), thecomputer as the measuring means stores in the memory MEM, the number oftimeslots, the number of carriers, and the number of spreading codes formodulation, used in transmission and receiving of packets, and the CPUas the calculating means calculates the amount of radio resources as acontribution from the values stored in the memory MEM. Namely, in thecase of the (W-)CDMA system, where the number of timeslots is 3 and thenumber of carriers in each frame is 10, the amount of radio resourcescan be calculated according to 3×10× (the number of spreading codesused).

In the case where the number of relay terminals for relaying packets istwo or more (including a case of series connection), the measuring meansof each relay terminal can also measure as the contribution a valueobtained by dividing a physical quantity used for communication at eachrelay terminal (the number of packets or the like), by the number ofrelay terminals. This results in decreasing the contribution of eachrelay terminal per communication, and it is thus feasible to preventincrease of the contribution or discount amount as a whole ofcommunication.

If the packet header is configured to contain addresses of interveningterminals, the number of addresses agrees with the number of relayterminals contributing to relaying. Contributions of the respectiverelay terminals can be set equal to each other in the case of the relayterminals being connected in series; however, in the case where thedifferent relay terminals are used between upward communication anddownward communication as described above, their contributions arenaturally different from each other and the contributions can bemeasured separately to the upward communication and to the downwardcommunication.

The above communication system is provided with the base station Z forrelaying the measurement result transmitted from the relay terminal tothe billing server SA. Namely, this transmission can be any transmissionby which the measurement result is eventually transmitted to the billingserver SA, and the measurement result does not have to be transmitteddirectly to the billing server SA.

The object to be transmitted from the relay terminals A, B does notalways have to be the raw measurement result, but may be a value to bededucted from the aforementioned information communication charge; thisvalue can be calculated from the measurement result by the CPU as thecalculating means. For example, it can be contemplated that the CPUranks a measurement result and transmits a value corresponding to itsrank to the billing server SA.

The above billing method comprises the step of transmitting from therelay terminal A, B the contribution to relaying by the relay terminalA, B for relaying packet communication between the destination terminalC existing outside the service area X of the base station Z, and thebase station Z; and the step of effecting negative billing calculationaccording to the contribution on the information communication chargestored in the predetermined storage device in the billing server SA, andthis billing method also enables provision of an incentive to the relayterminal A, B engaged in relaying for the other radio terminals Q, C.

The billing method in this case comprises the identification step ofidentifying whether the header included in the packets is one associatedwith relaying; and the step of incrementing the count number of theaforementioned counter in proportion to the number of packetstransmitted and/or received during relaying when the identification stepresults in identifying an occasion of relaying, and the aforementionedtransmission step is to transmit the value proportional to the countnumber as the contribution.

A specific detailed configuration of the relay terminal A will bedescribed below.

FIG. 6 shows the detailed configuration of the relay terminal Aconfigured to measure the contribution. The relay terminal A iscomprised of a radio transceiver A11, a measurement unit A12, ameasurement result processor A13, a measurement result transmissiontiming manager A18, a controller A16, and a route information managerA17. The radio transceiver A11 corresponds to the aforementionedtransmission device ATt and the other components to the CPU and memory.

The radio transceiver A11 transmits and receives packets, controlsignals, etc. to and from the base station Z and other terminals.

The measurement unit A12 measures a contribution to relaying. Forexample, in the control of FIG. 5, the measurement unit A12 manages thecounter to monitor transmission and receiving of relayed packets at thetransceiver A11; the result of the monitoring operation is thecontribution.

The measurement result processor A13 stores the measurement result bythe measurement unit A12 in correspondence to the identifier of theterminal A. In the case of multihop relaying described later, themeasurement result processor A13 calculates a final measurement resultas a contribution according to a hop count on the basis of theinformation about the hop count from the route information manager A17.

The measurement result transmission timing manager A18 manages thetiming of transmitting the measurement result to the incentivemanagement system SA2.

In response to a signal from the measurement result transmission timingmanager A18, the measurement result processor A13 transmits themeasurement result (with the identifier) to the radio transceiver A11and these are transmitted to the base station Z. The base station Ztransmits them to the incentive management system SA2.

In another conceivable configuration, the incentive management systemSA2 determines the transmission timing of the measurement result andsends the timing to the base station Z, the base station Z notifies therelay terminal A of the timing, and the notification is delivered to themeasurement result processor A13 through processing of the controllerA16 of the relay terminal A. In this configuration, the measurementresult processor A13 sends the measurement result on the basis of thenotification, and thus the relay terminal does not have to be equippedwith the measurement result transmission timing manager A18.

Since the controller A16 collects the information about the relay routemanaged by the route information manager A17, the relay terminal A needsto include it in order to transmit and receive control signals. Theinformation about the relay route collected herein is stored in theroute information manager A17. Since the information about the relayroute is information varying with time, the route information issuccessively updated. The configuration of the relay terminal B is thesame as that of the relay terminal A.

The configuration of the base station Z will be described below in thecase where the contribution is measured at the relay terminals.

FIG. 7 shows the configuration of the base station in the case where thecontribution is not measured at the base station Z. The base station Zconfigured not to measure the contribution (relay amount) is constructedin the simple configuration. A radio transceiver Z11 receives the resultof measurement by the relay terminal A, B and a measurement resultprocessor Z13 stores the measurement result in correspondence to theidentifier of the relay terminal. The measurement result is immediatelytransmitted via network IF (interface) Z14 and transceiver Z15 to theincentive management system SA2.

Another configuration of the base station Z will be described below inthe case where the base station Z is configured to measure thecontribution. In this case, the basic configuration of the base stationZ is the same as the configuration of the relay terminal shown in FIG. 2and the base station is further wired to the network N. The base stationZ is a base station configured to perform packet communication throughthe relay terminals A, B with the destination terminal C located outsidethe service area X thereof, and is provided with the measuring means asa computer for measuring the contribution to relaying by each relayterminal A, B, and the transmitting means (a transmission device fortransmission to the network N side: transceiver Z15 in FIG. 10) fortransmitting the measurement result to the billing server SA connectedto the network N including the base station Z and configured to storethe information communication charges of the relay terminals.

When the base station Z measures the contribution of the relay terminalA, B, the contribution is assumed to be the number of packetstransmitted to the relay terminal A and/or received from the relayterminal B. Namely, the computer as the measuring means of the basestation Z identifies whether the header included in the packets is oneassociated with relaying (identifying means), and is provided with acounter (an internal function of the computer of the base station Z) forincrementing its count number in proportion to the number of packetstransmitted to the relay terminal A and/or received from the relayterminal B during relaying when the identifying means identifies anoccasion of relaying, and the base station transmits a valueproportional to the count number as a measurement result of the numberof packets to the incentive management system SA2 of the billing serverSA.

The measurement method shown in FIG. 5 can also be applied to the casewhere the relay amount is measured at the base station Z. The counter iscounted up by one upon transmission and receiving of a relayed packet.When the counter up to K is counted up to K, it transmits an outputpulse (referred to as a count value) indicating completion of count-up.The count value and the identifier of the relay terminal are transmittedto the incentive management system SA2 connected to the network N. Thispoint is only the difference from the case where the measurement iscarried out at the relay terminals, and the number of packets can becalculated from the count value and the count number K.

The transmission device, which serves as the transmitting means of thebase station Z to perform transmission to the network N side, transmitsto the billing server SA the value proportional to the above countnumber as a measurement result along with the identification informationby the identifying means, and the inclusion of the identificationinformation enables the billing server SA to effect negative billing.

The contribution to relaying can also be a relay time of each relayterminal A, B. The computer as the measuring means of the base station Zidentifies whether a control message included in packets transmitted orreceived represents a start of communication or an end of communication(identifying means), calculates a time period between a receiving timeof the control message at the start of communication and a receivingtime of the control message at the end of communication, identified bythe identifying means, (calculating means), and transmits the timeperiod as a relay time of each relay terminal A, B to the billing serverSA.

In this case, where the base station performs packet communication witheach relay terminal A, B, the above control message is added to theheader on the occasion of transmission to the relay terminal A, and therelay terminal B is arranged to preliminarily add the above controlmessage to the header on the occasion of receiving.

For measuring the relay time, it is necessary to measure a period oftime from start to end of communication; in the case where the basestation relays control messages representing the start and end ofcommunication like a connection request message and a disconnectionrequest message, the start and end of measurement can be timed withreference to these messages.

The contribution can also be the amount of power internally consumed ineach relay terminal A, B during relaying. The measurement of the amountof internally consumed power can be conducted by letting each relayterminal A, B measure the amount of internally consumed power andletting the base station Z receive it; or the measurement may also beindirectly conducted by estimating the amount of internally consumedpower in each relay terminal A, B from the above relay time measured.The amount of internally consumed power can be determined moreaccurately if the model of each relay terminal A, B and/or the intensityof received waves from each terminal is measured or known.

The contribution measured at the base station Z can also be the amountof radio resources used by each relay terminal A, B.

When the communication system during relaying is TDMA, the computer ofthe base station Z as the measuring means stores in the memory MEM(memory means) the number of timeslots, the number of carriers, and thenumber of frames, used in transmission and receiving of packets to andfrom each relay terminal A, B, and calculates the amount of radioresources as a contribution by the same method as in the case where itis calculated at the relay terminals, from the values stored in thememory MEM (calculating means). During transmission to the relayterminal A, the base station can measure the number of timeslots used inthe transmission, the number of carriers included in each frame, and thenumber of frames used. The same also applies to the measurement duringreceiving from the relay terminal B.

When the communication system during relaying is CDMA, the computer ofthe base station Z as the measuring means stores the number of timeslotsused in transmission and receiving of packets, the number of carriersincluded in each frame, and the number of spreading codes in the memoryMEM, and calculates the amount of radio resources as the abovecontribution from the values stored in the memory MEM (calculatingmeans). The technique of the calculation is much the same as the methodof calculation at each relay terminal A, B.

When the number of relay terminals for relaying packets is two or more(including the case of series connection), the transmitting means fortransmitting the measurement result to the network interface side of thebase station Z transmits a value obtained by dividing a physicalquantity used in each relay terminal (the number of packets or thelike), by the number of relay terminals, along with the informationabout the corresponding relay terminal (identifier) to the billingserver SA. This function is much the same as in the case of the relayterminals. When the relay terminals are connected in series, the numberof addresses of intervening terminals in the header included in thepackets transmitted to the relay terminal during transmission agreeswith the number of relay terminals.

There are a variety of techniques of measuring the contribution.

FIG. 8 shows an example of measurement to measure the relay amount atthe base station Z. In the case where the base station Z measures therelay amount, it measures contributions in both the downwardcommunication and upward communication. The base station needs to managethe results of measurement by the base station Z and the identifiers ofthe relay terminals A, B during transmission and receiving carried outby the base station Z. For this reason, the base station Z has amanagement table (memory MEM) for managing the measurement results incorrespondence to the identifiers of the terminals A, B and regularlytransmits the information in the management table to the incentivemanagement system SA2 connected to the network N. The management tableis reset after the transmission.

The multihop communication case will be described below.

Suppose packets were transmitted through the relay route as shown inFIG. 9. In the multihop communication case where there exist a pluralityof relay terminals between the base station Z and the destinationterminal C, when each relay terminal measures the relay amount, ittransmits a value obtained by dividing a physical quantity (the numberof packets or the like) used during relaying, by a hop count, as a finalmeasurement result (contribution) to the incentive management systemSA2. Of course, the measurement result is transmitted via the basestation Z in the case where the measurement is carried out at the relayterminals.

There exist the relay terminals A, B, D, and E between the base stationZ and the destination terminal C. The relay route of packets in the downdirection from the base station Z to the destination terminal C is basestation Z→A→B→D→destination terminal C. The relay route of packets inthe up direction from the destination terminal to the base station isdestination terminal C→D→E→base station Z.

At this time, let Ma, Mb, and Me be physical quantities utilized forrelaying at the respective terminals A, B, and E, Mdup be a physicalquantity utilized for upward relaying at the relay terminal D, and Mddnbe a physical quantity utilized for downward relaying at D. Then finalmeasurement results (contributions) at the respective terminals are asfollows.

TABLE 1 Terminal A; Ma/3 Terminal B; Mb/3 Terminal D; Mddn/3 + Mdup/2Terminal E; Me/2

In the multihop communication case where there exist a plurality ofrelay terminals between the base station Z and the destination terminalC, as described above, the measurement at the relay terminals can beimplemented as follows: each relay terminal counts the hop count up andrewrites the header of packets, and it is reversely notified of thefinal hop count at the destination terminal C or at the base station Z,whereby the relay terminals can share the information about the hopcount of relaying.

In the present example, where the number of relay terminals for relayingpackets is two or more, for example, the measuring means of the relayterminal D, concerning each of the upward communication and downwardcommunication, measures as the contribution the value obtained bydividing the physical quantity (Mdd) used in communication at the relayterminal D, by the number of relay terminals (3 in the down direction or2 in the up direction), and the transmitting means of the relay terminalD transmits this value to the billing server SA.

On the other hand, in the case of the system being one in which the basestation Z manages the information about the relay route, it is alsofeasible to implement a configuration in which the base station Zmeasures and manages the relay amount of each relay terminal on thebasis of the route information held by the base station Z, withoutnotifying the relay terminals of the hop count of relaying. The relayterminals or the base station Z acquires the hop count from theinformation about the relay route.

Namely, in the case where the base station Z is configured to measurethe relay amount and where the number of relay terminals for relayingpackets is two or more, the relay route (the number of terminals or thehop count) in the downward direction from the base station Z side andthe relay route (the number of terminals or the hop count) in the upwarddirection from the base station Z side are known.

The number of packets transmitted from the base station Z in thedownward communication case, as the above physical quantity, is dividedby the number of terminals in the relay route of the downwardcommunication and the number of packets arriving at the base station Zin the upward communication case is divided by the number of terminalsin the relay route of the upward communication; for example, thecontributions about the relay terminal D can be measured ascontributions Mddn/3 and Mdup/2.

In other words, in the present example, where the number of relayterminals for relaying packets is two or more, for example, the basestation Z is arranged as to each of the upward communication anddownward communication, for example, about the relay terminal D so thatthe measuring means thereof measures the value obtained by dividing thephysical quantity (Mdd) used in communication at the relay terminal D,by the number of relay terminals (3 in the down direction or 2 in the updirection), as the aforementioned contribution and transmits this valueto the billing server SA.

In such case, the total contribution is set to a predetermined value,whereby it is feasible to prevent the total incentive amount fromincreasing excessively.

When the incentive management system SA2 of the billing server SAreceives the contribution (measurement result) to relaying by each relayterminal A, B, as described above, the incentive management system SA2calculates an incentive amount, and transmits this incentive amount tothe billing management system SA1 to effect negative billing at thebilling management system SA1; or the incentive management system SA2retrieves the information communication charge stored in the billingmanagement system SA1 and effects negative billing.

Namely, the billing server SA is a computer for storing the informationcommunication charges of the relay terminals A, B, and the billingserver SA receives the contribution to relaying by the relay terminal A,B for relaying packet communication between the destination terminal Clocated outside the cell X of the base station Z, and the base station Zfrom the base station Z side (receiving means) and effects negativebilling according to the contribution received by the receiving means,on the information communication charge of each relay terminal A, Bstored.

In other words, the billing server SA calculates the incentive amountaccording to the contribution and deducts this incentive amount from theinformation communication charge. The incentive amount is calculated asfollows: a quantity indicating a level of relaying measured at the basestation Z or at each terminal, i.e., the relay amount (contribution) isstored in the incentive management system SA2 on the network N and thecalculation operation is carried out in the system.

A detailed configuration of the base station Z will be described below.

FIG. 10 shows the configuration of the base station where the basestation Z measures the relay amount, and in the case of measuring thecontribution, the base station Z is comprised of a radio transceiverZ11, a measurement unit Z12, a measurement result processor Z, ameasurement result transmission timing manager Z18, a controller Z16, anetwork IF part Z14, a transceiver Z15, and a route manager 17. Theradio transmitter Z11 corresponds to the transmission device ATt in FIG.2, and the other components to the CPU and memory MEM.

The radio transceiver Z11 transmits and receives packets, controlsignals, etc. to and from the aforementioned relay terminals. Themeasurement unit Z12 is a part for measuring the contribution. Forexample, in the example shown in FIG. 5, the measurement unit managesthe counter to monitor the transmission and receiving of relayed packetsat the transceiver Z15; as a result of the monitoring, the valueproportional to the count number is obtained as a measurement result.

The measurement result processor Z13 stores the measurement result bythe measurement unit Z12 in correspondence to the identifier of therelay terminal, and calculates a final measurement result as a relayamount according to a hop count on the basis of the information aboutthe hop count from the route information manager Z17 in the case ofmultihop relaying.

The measurement result transmission timing manager Z18 manages thetiming of transmission of the measurement result to the incentivemanagement system SA2. In response to a signal from the measurementresult transmission timing manager Z18, the measurement result processorZ13 sends the measurement result (with the identifier) via the networkIF part Z14 and transceiver Z15 to the incentive management system SA2.

It can also be contemplated that the incentive management system SA2determines the transmission timing of the measurement result andnotifies the base station Z of the timing; in this case, the basestation does not have to be equipped with the measurement resulttransmission timing manager Z18.

Since the controller Z16 collects the information about the relay routemanaged by the route information manager Z17, the base station has to beequipped with the controller Z16 in order to transmit and receivecontrol signals to and from the relay terminals. The information aboutthe relay route collected herein is stored in the route informationmanager Z17. Since the information about the relay route is informationvarying with time, the route information is successively updated.

FIG. 11 shows a configuration of the incentive management system SA2.The incentive management system SA2 is comprised of a transceiver SA11,a measurement result processor/storage SA12, an incentive leveldeterminer SA13, an incentive amount determiner SA14, a chargecalculator SA16, a point storage SA15, and a setting display SA17, andis constructed of a computer.

The transceiver SA11 receives the measurement result of the contributionfrom the base station Z via the network N and transmits the controlsignals including a response thereto and others.

The measurement result processor/storage SA12 receives the receivedmeasurement result of contribution from the transceiver SA11, rearrangesdata in order of levels of measurement results, and stores the receivedresult in correspondence to the identifier of the relay terminal A, B.

The incentive level determiner SA13 performs grouping of the measurementresult on the basis of a predetermined reference value for themeasurement result and maps each group onto an incentive level.

The incentive amount determiner SA14 calculates an incentive amount ofeach incentive level on the basis of predetermined weight and base unitof incentive amount. The incentive levels and the calculation ofincentive amount will be detailed later.

The charge calculator SA16 calculates a charge amount according to thecharge amount calculation flow described later and shown in FIGS. 12 and13. The charge calculator SA16 receives the information about theinformation communication charge of each terminal A, B from the billingmanagement system SA1 via the transceiver SA11 and uses it for thecalculation of charge amount. The result of the calculation of chargeamount is sent via the transceiver SA11 to the billing management systemSA1.

The point storage SA15 stores points as past incentive amounts held, incorrespondence to holding periods and identifiers of relay terminals.

The charge calculator SA16 acquires the point information from the pointstorage SA15 and performs a calculation process according to the chargeamount calculation flow shown in FIGS. 12 and 13. The charge calculatorSA16 transmits a new point calculated based on the charge calculationflow, to the point storage SA15, and the point storage SA15 stores thepoint information.

The setting display SA17 has an input interface through which parametersto be preliminarily set, such as the reference value of the measurementresult used in the grouping, the weights, the base unit (U) of theincentive amount, etc., can be set from the outside, and an outputinterface for display of the setting result and calculation result. Theparameters set herein are transmitted via the charge calculator SA16 toeach processing part.

There are a variety of conceivable techniques of calculating theincentive amount. Three calculation techniques will be detailed below.

The first method is a method of determining a fixed incentive amount.The present method is a method of providing a fixed value as anincentive amount to a relay terminal having performed relaying with ameasurement of a contribution (relay amount) being not less than acertain value (hereinafter referred to as a reference value S). Thismethod can be implemented by setting the reference value S and anincentive amount T for the reference value S in the incentive managementsystem SA2.

The incentive management system SA2 compares the received measurementresult of the contribution (relay amount) with the reference value S anddetermines the incentive amount of T only when the measurement result ofthe relay amount is greater than the reference value. Namely, in thepresent example, when the level of the contribution of each relayterminal received by the incentive management system SA2 is not lessthan the reference value S, the amount of negative billing in thebilling management system SA1 or in the incentive management system SA2is set at the given value T. Since the present method achieves simpledetermination of the incentive amount, it can lessen the processing ofthe incentive management system SA2.

The second method is a method of determining a weighted incentiveamount. The present method is a method of determining an incentiveamount according to a relay amount measured, in which a measurementresult of a contribution is mapped onto a map defining incentive levelsand is weighted according to a corresponding level and in which anincentive amount is then determined based on the weighted contribution.The flow of determination of the weighted incentive amount (1) to (4)will be described below.

(1) First, grouping into groups Gi is carried out based on measurementresults of contributions. A case of grouping into five groups will bedescribed below as an example. The number of terminals belonging to eachgroup Gi is denoted by MSi. The population of grouping is a set of aplurality of practical measurement results. The size of the populationis appropriately set.

(2) Incentive levels Li are set in five steps (i=5), and the groups Giare mapped onto the incentive levels Li. In this case, the measurementresults of contributions are arranged in descending order, and a group(rank) Gi is determined based on in which top percentage range aterminal in question falls relative to the total number of terminals forwhich incentive amounts are to be determined. This method yields thefollowing mapping.

TABLE 2 top 20%; rank G1 → incentive level L1 top 20%-40%; rank G2 →incentive level L2 top 40%-60%; rank G3 → incentive level L3 top60%-80%; rank G4 → incentive level L4 top 80%-100%; rank G5 → incentivelevel L5

In another potential way, a maximum measurement result of relay amountis extracted from the entire set, the measurement result groups Gi inthe ranges of not less than 80%, 80%-60%, 60%-40%, 40%-20%, and 20%-0%of the maximum are generated on the basis of the maximum, and the groupGi can be determined based on in which group among them the measurementresult of the terminal in question falls.

(3) Then weights Wi are given to the respective incentive levels asfollows. It is assumed herein that there is the relation of1<W1<W2<W3<W4<W5. Terminals in the same group are given the same weight.

TABLE 3 incentive level L1 → weight W1 incentive level L2 → weight W2incentive level L3 → weight W3 incentive level L4 → weight W4 incentivelevel L5 → weight W5

(4) Incentive amounts Ti are determined according to the incentivelevels Li as follows. The base unit U of incentive amount herein is abasic incentive amount per terminal and is a value preliminarily set inthe incentive management system SA2 as the weights Wi were.

TABLE 4 incentive level L1 → T1 = weight W1 × base unit U of incentiveamount incentive level L2 → T2 = weight W2 × base unit U of incentiveamount incentive level L3 → T3 = weight W3 × base unit U of incentiveamount incentive level L4 → T4 = weight W4 × base unit U of incentiveamount incentive level L5 → T5 = weight W5 × base unit U of incentiveamount

With processing according to the above flow, the total incentive amountgiven to all the terminals for one month (predetermined period), ΣALL,is given by Eq (1) below.

$\begin{matrix}{{\sum{ALL}} = {\sum\limits_{i = 1}^{N}{\left( {{MSi} \times {Wi}} \right) \times U}}} & (1)\end{matrix}$

In the mobile communication systems handling multimedia, service itemsare expected to grow increasingly diverse. For example, the servicecontents become diverse, e.g., a fast communication service at aspecific speed ensured, a best effort communication service to implementcommunication only in the presence of radio resources, autilization-time-limited service, etc., and billing ways also becomediverse corresponding thereto. In such cases, incentive amounts have tobe determined according to the service contents.

For this purpose, the incentive management system SA2 can effectweighting based on information of those service contents in addition tothe measurement results of contributions to determine the incentiveamounts.

Since the determining method of the weighted incentive amount determinesthe incentive amounts according to contributions, it is a determiningmethod equitable to the terminals.

This method is a method of classifying a contribution of a relayterminal (a total over a predetermined period) into one group among aplurality of groups separated according to contributions from a set ofcontributions of relay terminals and effecting the aforementionednegative billing on the basis of a value of a weighting factorcorresponding to each group correlated with the base fee.

Let n be the number of groups utilized in different periods in themapping for one relay terminal. The billing server SA classifies each ofcontributions (relay amounts) in the different periods of each relayterminal, into a group set of groups Gi separated according tocontributions from a set of contributions of relay terminals, correlatesweighting factors corresponding to the respective groups, with the baseunit (base fee) U and adds up them to obtain an incentive amount, andthen deducts it from the information communication charge, therebyeffecting negative billing. The correlation in the present example ismultiplication, and by replacing N with n in the right-hand side of Eq(1), we can obtain the incentive amount ALL for one month of oneterminal.

The third method is a method of determining the incentive amount on thebasis of expenditure of an information communication charge of atelecommunications carrier. If the area coverage is low, or ifcommunication is done via a number of relay terminals, the incentiveamount paid to the relay terminals can become greater than theinformation communication charge collected from subscribers by thetelecommunications carrier. In such cases, use of the third methodpermits the total ΣALL of incentive amounts to all the terminals to belimited to below a certain value or below ΣALL(limit).

Namely, the present method is a method of allocating up to the upperlimit of incentive amount ΣALL(limit) to terminals contributing torelaying. The allocation to terminals is adapted to each of theforegoing first and second incentive determination methods. Namely, theamount of negative billing effected at the billing server SA is set tobe not more than the predetermined maximum amount.

In the determination method of the fixed incentive amount being thefirst method, for example, supposing there are two hundred terminalsserving for relaying at or above a given quantity, the upper limit isequally allocated to all the two hundred terminals as objects,ΣALL(limit)÷200, and the equally divided amounts are determined asincentive amounts.

Furthermore, in the case of the determination method of the weightedincentive amount being the second method, the incentive amount can bedetermined as follows. From Eq (1), the relationship of ΣALL(limit) withWi and MSi is given by Eq (2) below. It is, however, assumed that Nrepresents the total number of terminals and all relay amounts over apredetermined period per relay terminal are added up.

$\begin{matrix}{{\sum{{ALL}({limit})}} \geq {\sum\limits_{i = 1}^{N}{\left( {{MSi} \times {Wi}} \right) \times U}}} & (2)\end{matrix}$

Here MSi are determined by the foregoing flow (1) to (2) and Wi arepreliminarily set in the incentive management system SA2 as describedpreviously. From the relationship of Eq (2), the base unit U ofincentive amount can be calculated as in Eq (3) below.U=ΣALL(lim it)/(MSi×Wi)  (3)

By executing the process of the foregoing flow (4) using the calculatedvalue of U, we can obtain the incentive amount of each relay terminal.With use of the present method, the allocation of incentive amounts isfair, because the determining method of the incentive amount accordingto the relay amount is applied; in addition, because the upper limit isset to the total incentive amount, the incentive amount can be set so asto prevent the incentive amount paid to the relay terminals fromexceeding the information communication charge collected fromsubscribers by the telecommunications carrier.

The foregoing billing method of the information communication chargecomprises the step of storing the information communication charge ofthe relay terminal in the storage device of the billing server SA; thestep of receiving the contribution to relaying by the relay terminal forrelaying packet communication between the destination terminal Cexisting outside the service area of the base station Z, and the basestation Z; and the step of effecting the negative billing calculationaccording to the received contribution on the information communicationcharge stored in the storage device, and is executed in the billingserver SA.

In the above embodiment, since the contribution to relaying is measured,it can be reflected in the billing; since the negative billing iseffected in the billing server SA, it is feasible to implement provisionof the incentive to the relay terminal. The amount of negative billingmay also be set to a value proportional to the level of the contributionto relaying.

The billing server SA is constructed of a computer, and a programinstalled in this computer is a program for letting the computerexecute: the step of storing the information communication charge of therelay terminal in the storage device; and the step of receiving thecontribution to relaying by the relay terminal A, B for relaying packetcommunication between the destination terminal C located outside theservice area of the base station Z, and the base station Z and effectingthe negative billing calculation according to the received contributionon the information communication charge stored in the storage device.For installing the program into the computer, a recording medium inwhich the program is recorded so that the computer can read, is set in areading device of the computer, and the program is read thereby.

This program or any program for executing the methods described in thepresent specification can be transmitted while being included in acarrier wave. The program thus transmitted is read by the computer andthe computer executes the processing thereof. For example, a computerdata signal in the case of the above program is a computer data signalincluded in a carrier wave, which makes the computer having read thesignal, execute: the step of storing the information communicationcharge of the relay terminal in the storage device; and the step ofreceiving the contribution to relaying by the relay terminal forrelaying packet communication between the destination terminal and thebase station and effecting the negative billing calculation according tothe received contribution on the information communication charge storedin the storage device.

The incentive amount calculated by the foregoing determination flow ofthe incentive amount is reflected in the information communicationcharge of the relay terminal, and a charge which a subscriber has to payto the telecommunications carrier in fact is basically a differenceobtained by subtracting a calculated incentive amount from aninformation communication charge for communication conducted by theterminal. This process is carried out in the billing management systemSA1.

The calculation can be done at regular intervals, or once a month, andthe final charge can be determined based thereon. However, when thecalculated incentive amount is compared with the informationcommunication charge for communication conducted by the terminal, thecalculated incentive amount can be greater in certain cases. In suchcases the charge to the subscriber can be determined to zero.

When the result of calculation of the charge for a specific month isthat the calculated incentive amount is greater than the informationcommunication charge for communication by the terminal, it is alsopossible to provide a service of retaining the incentive amount for awhile and carry the excess incentive amount over to the next calculationtiming (e.g., the next month).

Namely, in the case where the amount of negative billing is greater thanthe information communication charge stored in a predetermined period,the billing server SA stores the difference between them for a certainperiod and effects the negative billing on the next informationcommunication charge on the basis of the stored value. In this case, thenegative billing not used can be carried over to the next time, wherebyit is feasible to promote interests of the telecommunications carrierand users.

FIG. 12 shows the flow in this case. An incentive amount held will bereferred to hereinafter as a point. Let us suppose one relay terminalholds three past points P1, P2, and P3. In the case where three pastpoints can be held, a charge amount reflecting the points is calculated.The present processing is carried out for determining a charge amount ofa certain terminal in the incentive management system SA2, and chargeamounts of all terminals can be determined by repeating similarprocessing for the terminals of all subscribers.

First, information about an information communication charge A1 of acertain terminal is acquired from the billing management system SA1(S1). The information communication charge A1 is a charge for onlyconduct of communication, which reflects no incentive yet. Then anincentive amount Z1 is determined according to the aforementioneddetermination flow of incentive amount (S2). The system acquires thethree past points P1, P2, and P3 of this terminal (S3). The point in theoldest period is P3 and the latest point is P1.

The sum of Z1+P1+P2+P3 is compared with the information communicationcharge A1 (S4). Since the sum of Z1+P1+P2+P3 is the total of the currentincentive amount and all the points held, it gives an aggregate sum ofincentive amounts that can be utilized in the present processing by theterminal.

When the sum of Z1+P1+P2+P3 is smaller, it means that the informationcommunication charge A1 is greater than the total available incentive,and the charge A1 finally billed is calculated as a difference betweenthe sum of Z+P1+P2+P3 and the original A1 (S5).

On the other hand, when the sum of Z+P1+P2+P3 is greater, a point heldas an incentive available in the next period can be determined from aremainder resulting from subtraction of A1 from the sum of Z+P1+P2+P3.

However, since only three past points can be held herein, current P3cannot be utilized in the next period. For this reason, in order to keepthe amount held in the next period as large as possible, the points areused in order from the oldest on the occasion of subtracting theinformation communication charge A1 from the available incentive.

Therefore, P3 is compared with A1 (S6). If A1 is greater, the value ofA1−P3 replaces A1 (S7) and is then compared with P2 (S9). Since this isthe case where the information communication charge A1 is greater thanthe oldest point P3, the process here is a process for using P3 entirely(or setting P3 to zero (S8)) and also using the next oldest point.

When the result of the comparison between P2 and A1 is that A1 isgreater again, the result of subtraction of P2 from replaced A1, furtherreplaces A1 (S10). Since the next oldest point P2 is also used up atthis stage, P2 is also set to zero (S11).

The processing as described above is also repeated for P1 and Z1.

Namely, P1 is further compared with A1 (S12). When the result of thecomparison is also that A1 is greater again, the result of subtractionof P1 from replaced A1, further replaces A1 (S13). Since the point P1 isalso used up at this stage, P1 is set to zero as well (S14).

Finally, the present incentive amount Z1 is compared with A1 (S15). Whenthe result of the comparison is that A is greater again, the result ofsubtraction of Z1 from replaced A1, further replaces A1 (S16). Since theincentive amount Z1 is also used up at this stage, Z1 is set to zero aswell (S17).

A1 obtained as a result of the processing heretofore is the differenceresulting from the operation of subtracting the points P3, P2, P1, andZ1 in order from the original information communication charge A1 and isthe charge A1 finally billed.

On the other hand, during the stages of using the points in order fromthe oldest, A can be smaller than a certain point. For example, thiscorresponds to the case where, in the comparison between P3 and A1 (S4),A1 is smaller than P3. In this case, there remains some point even afteruse of the point P3 and the charge A1 billed is set at zero (S61). Theremaining point after subtraction of A1 from P3 is tentativelysubstituted into P3 (S61). At this stage, there is no change in thevalues of P2, P1, and Z1.

When A1 is smaller in the comparison between P2 and A1 (S9) in theforegoing flow, there remains some point even after use of the point P2.The remaining point of P2−A1 is tentatively substituted into P2 (S91)and the charge A1 billed is set at zero (S92). At this stage, P3 iszero, but there is no change in the values of P1 and Z1.

When A1 is smaller in the comparison between P1 and A1 (S12), thereremains some point even after use of the point P1. The remaining pointof P1−A is tentatively substituted into P1 (S121) and the charge A1billed is set at zero (S122). At this stage, P3 and P2 are zero, butthere is no change in the value of Z1.

When A1 is smaller in the comparison between Z1 and A (S15), thereremains some point even after use of Z1. The remaining point of Z1−A istentatively substituted into Z1 (S151) and the charge A1 billed is setat zero (S152). At this stage, P3, P2, and P1 are zero.

Since the original information communication charge was smaller than thesum of the points and incentive amount, A1 obtained as a result of thisprocessing becomes zero.

FIG. 13 shows the flow in the case where A1 becomes zero, as describedabove, and it starts from substep SS1. In order to hold new pointsnecessary in the timing of calculation of the next charge amount, theoldest point P3 is rewritten into P4, the next oldest point P2 into theoldest point P3, the point P1 into the point P2, and the presentincentive amount Z1 into the latest point P1, and the incentive amountZ1 is set to 0 (SS10).

Since the points P1, P2, and P3 obtained as a result are held as newpoints utilized in the next calculation timing, they are fed to andstored in a point storage area in the storage device. Then this flow isterminated (SS2) and the processing returns to FIG. 12 to display orstore the charge A1 (S18).

As described above, the above system can substantiate implementation ofthe mobile communication systems in which the ad hoc network is appliedto the public services and in which the services can be provided toterminals located in areas that cannot be covered by any base station.Namely, while a subscriber's terminal is serving to assist communicationfor others, some load is exerted on communication of the subscriber;this made it difficult to apply the ad hoc network to the publicservices. In contrast to it, the present system gives an incentive to aterminal involved in relaying so as to serve to assist communication ofothers, whereby the load of relaying can be relieved on the subscriber.

For this reason, the telecommunication carriers do not have to spendmoney for impractical capital investment for covering sites where radiowaves are unlikely to reach, with service areas, and it becomes feasibleto implement virtual expansion of the original service areas by makinguse of the subscriber's terminals. On the other hand, the subscribersare given incentives as compensations for application of their ownterminals to communications for others, whereby the informationcommunication charges paid to the carriers can be decreased.

Since the weighted incentives are calculated according to the respectiverelay amounts, it is feasible to ensure fairness among the relayterminals. Since the various parameters necessary for the calculation ofincentive amounts, e.g., for the weighting, are set from the outside,the system is superior in flexibility.

Furthermore, since the upper limit of the total incentive amount is set,the incentive amount paid to the relay terminals can be prevented fromexceeding the information communication charge collected from thesubscribers by the telecommunications carrier.

If in the calculation of the charge billed at regular intervals theincentive amount is greater than the actual information communicationcharge, the difference of the information communication charge from theincentive amount is stored for the fixed period and the incentive amountthus stored is reflected in the billed charge on the occasion ofcalculating the next billed charge; therefore, the available period ofincentive can be lengthened. In this case, the possibility of capabilityof using the incentive becomes higher even if a period of serving torelaying is different from a period of carrying out a lot ofcommunications. The aforementioned program can be transmitted in theform of the computer data signal included in the carrier wave, to therelay terminal and be executed in the relay terminal.

The relay terminal, base station, billing server, communication system,billing method, computer data signal, program, and storage mediumaccording to the present invention made it feasible to provide theincentive to the radio terminal engaged in relaying for the other radioterminals, on the public network to which the ad hoc technology isapplied.

FIG. 14 is a system configuration diagram according to an embodiment.The present example illustrates a case where the destination terminal Cis located within the service area (cell X) of the base station Z. Inthis case, when the terminal Q transmits a signal to the destinationterminal C, the relay terminals A, B can relay the signal. In this case,instead of identifying whether the destination terminal C is locatedoutside the cell X, it is identified whether the destination terminal Cis, for example, in a state in which a relayed signal is weak, thoughbeing located in the cell X, and in the case where the destinationterminal is in this state, the relay terminals A, B relay the signal.The other system configuration is the same as described above.

INDUSTRIAL APPLICABILITY

The present invention is applicable to the relay terminals, basestations, billing servers, communication systems, billing methods,computer data signals, programs, and storage media.

1. A relay terminal for relaying packet communication between adestination terminal and a base station, said relay terminal comprising:measuring means for measuring a contribution to the relaying; andtransmitting means for transmitting a measurement result of thecontribution to a billing server connected to a network including thebase station and configured to store an information communication chargeof the relay terminals, wherein when there are a plurality of relayterminals for relaying packets, the measuring means of each relayterminal measures as the contribution a value obtained by dividing aphysical quantity used for communication in each relay terminal, by thenumber of relay terminals.
 2. The relay terminal according to claim 1,wherein said measuring means comprises identifying means for identifyingwhether a header included in the packets is one associated withrelaying; and a counter configured to increment a count number thereofin proportion to the number of packets transmitted and/or receivedduring relaying when the identifying means identifies an occasion ofrelaying, and wherein a value proportional to the count number istransmitted as a measurement result of the number of packets to thebilling server.
 3. The relay terminal according to claim 2, wherein thetransmitting means transmits the value proportional to the count numberalong with identification information obtained by the identifying means,as the measurement result to the billing server.
 4. The relay terminalaccording to claim 1, wherein the measuring means comprises identifyingmeans for identifying whether a control message included in the packetsrepresents a start of communication or an end of communication; andcalculating means for calculating a time period between a receiving timeof the control message at the start of communication and a receivingtime of the control message at the end of communication, identified bythe identifying means, and wherein said time period is transmitted assaid relay time to the billing server.
 5. The relay terminal accordingto claim 1, wherein a communication system during the relaying is timedivision multiple access, and wherein the measuring means comprisesstorage means for storing the number of timeslots, the number ofcarriers, and the number of frames, used in transmission and receivingof the packets; and calculating means for calculating the amount ofradio resources as the contribution from the values stored in thestorage means.
 6. The relay terminal according to claim 1, wherein acommunication system during the relaying is code division multipleaccess, and wherein the measuring means comprises storage means forstoring the number of timeslots, the number of carriers, and the numberof codes, used in transmission and receiving of the packets; andcalculating means for calculating the amount of radio resources as thecontribution from the values stored in the storage means.
 7. Acommunication system comprising a base station for relaying themeasurement result transmitted from the relay terminal as set forth inclaim 1 to the billing server.
 8. The relay terminal according to claim1, wherein when the destination terminal is located outside a servicearea of the base station, the measuring means measures the contribution.9. A base station for implementing packet communication with adestination terminal through a relay terminal, said base stationcomprising: measuring means for measuring a contribution to relaying bythe relay terminal; and transmitting means for transmitting ameasurement result of the contribution to a billing server connected toa network including the base station and configured to store aninformation communication charge of the relay terminal, wherein whenthere are a plurality of relay terminals for relaying packets, themeasuring means of each relay terminal measures as the contribution avalue obtained by dividing a physical quantity used for communication ineach relay terminal, by the number of relay terminals.
 10. The basestation according to claim 9, wherein when the destination terminal islocated outside a service area of the base station, the measuring meansmeasures the contribution.
 11. A billing server for storing aninformation communication charge of a relay terminal, said billingserver comprising: receiving means for receiving a contribution torelaying by the relay terminal for relaying packet communication betweena destination terminal and a base station; and billing means foreffecting negative billing according to the contribution received by thereceiving means, on the information communication charge stored, whereinwhen the contribution is not less than a reference value, an amount ofthe negative billing is set to a given value.
 12. The billing serveraccording to claim 11, wherein when the destination terminal is locatedoutside a service area of the base station, the receiving means receivesthe contribution.
 13. A billing server for storing an informationcommunication charge of a relay terminal, said billing servercomprising: receiving means for receiving a contribution to relaying bythe relay terminal for relaying packet communication between adestination terminal and a base station; and billing means for effectingnegative billing according to the contribution received by the receivingmeans, on the information communication charge stored, wherein an amountof the negative billing is set to a value proportional to a level of thecontribution.
 14. A billing server for storing an informationcommunication charge of a relay terminal, said billing servercomprising: receiving means for receiving a contribution to relaying bythe relay terminal for relaying packet communication between adestination terminal and a base station; and billing means for effectingnegative billing according to the contribution received by the receivingmeans, on the information communication charge stored, wherein an amountof the negative billing is set at or below a predetermined maximumamount.
 15. A billing server for storing an information communicationcharge of a relay terminal, said billing server comprising: receivingmeans for receiving a contribution to relaying by the relay terminal forrelaying packet communication between a destination terminal and a basestation; and billing means for effecting negative billing according tothe contribution received by the receiving means, on the informationcommunication charge stored, wherein the contribution by the relayterminal is classified into one group out of a plurality of groupsobtained by dividing a set of contributions of relay terminals accordingto the contributions, and wherein the negative billing is effected basedon a value of a base amount correlated with a weighting factorcorresponding to each group.
 16. The billing server according to claim15, wherein said correlation is multiplication.
 17. A billing server forstoring an information communication charge of a relay terminal, saidbilling server comprising: receiving means for receiving a contributionto relaying by the relay terminal for relaying packet communicationbetween a destination terminal and a base station; and billing means foreffecting negative billing according to the contribution received by thereceiving means, on the information communication charge stored, whereinwhen an amount of the negative billing is greater than the informationcommunication charge stored in a predetermined period, a differencebetween the information communication charge and the amount of thenegative billing is stored for a fixed period and the negative billingis effected on a next information communication charge on the basis ofthe stored difference.
 18. A billing method of an informationcommunication charge comprising: storing an information communicationcharge of a relay terminal in a storage device; receiving a contributionto relaying by the relay terminal for relaying packet communicationbetween a destination terminal and a base station; and effectingnegative billing calculation according to the received contribution onthe information communication charge stored in the storage device,wherein when the contribution is not less than a reference value, anamount of the negative billing is set to a given value.
 19. A computerdata signal included in a carrier wave, said computer data signalletting a computer having read the signal, execute: storing aninformation communication charge of a relay terminal in a storagedevice; and receiving a contribution to relaying by the relay terminalfor relaying packet communication between a destination terminal and abase station and effecting negative billing calculation according to thereceived contribution, on the information communication charge stored inthe storage device, wherein when the contribution is not less than areference value, an amount of the negative billing is set to a givenvalue.
 20. A relay terminal for relaying packet communication between adestination terminal and a base station, said relay terminal comprising:measuring means for measuring a contribution to the relaying; andcalculating means for calculating from a measurement result by themeasuring means, a value to be deducted from an informationcommunication charge in a billing server connected to a networkincluding the base station and configured to store the informationcommunication charge of the relay terminal, wherein when thecontribution is not less than a reference value, the value to bededucted corresponds to negative billing which is set to a given value.21. The relay terminal according to claim 20, wherein when thedestination terminal is located outside a service area of the basestation, the measuring means measures the contribution.
 22. A billingmethod of an information communication charge comprising: transmitting acontribution to relaying by a relay terminal for relaying packetcommunication between a destination terminal and a base station, fromthe relay terminal; and effecting negative billing calculation accordingto the contribution, on an information communication charge stored in apredetermined storage device, wherein when the contribution is not lessthan a reference value, an amount of the negative billing is set to agiven value.
 23. The billing method of the information communicationcharge according to claim 22, comprising an identification step ofidentifying whether a header included in the packets is one associatedwith relaying; and a step of incrementing a count number of a counter inproportion to the number of packets transmitted and/or received duringrelaying when the identification step results in identifying an occasionof relaying, wherein the transmitting step is to transmit a valueproportional to the count number as the contribution.
 24. A program forletting a computer execute a step of storing an informationcommunication charge of a relay terminal in a storage device; and a stepof receiving a contribution to relaying by the relay terminal forrelaying packet communication between a destination terminal and a basestation and effecting negative billing calculation according to thereceived contribution on the information communication charge stored inthe storage device, wherein when the contribution is not less than areference value, an amount of the negative billing is set to a givenvalue.